diff --git a/trunk/src/core/srs_core_client.cpp b/trunk/src/core/srs_core_client.cpp
index ec16b95fc..d066128f4 100644
--- a/trunk/src/core/srs_core_client.cpp
+++ b/trunk/src/core/srs_core_client.cpp
@@ -62,6 +62,7 @@ SrsClient::~SrsClient()
 	srs_freep(refer);
 }
 
+// TODO: return detail message when error for client.
 int SrsClient::do_cycle()
 {
 	int ret = ERROR_SUCCESS;